Browsing by Author "Borrell Pol, Ricard"

Now showing items 1-20 of 61

    • A dynamic load balancing method for the evaluation of chemical reaction rates in parallel combustion simulations 

      Muela Castro, Jordi; Borrell Pol, Ricard; Ventosa Molina, Jordi; Jofre Roca, Lluís; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David (Elsevier, 2019-08-15)
      Article
      Open Access
      The development and assessment of an efficient parallelization method for the evaluation of reaction rates in combustion simulations is presented. Combustion simulations where the finite-rate chemistry model is employed ...

    • A load balancing method for parallel genetic CFD optimizations 

      Aizpurua Udabe, Imanol; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2015)
      Conference report
      Restricted access - publisher's policy
      CFD optimizations are characterized by long and highly variable objective function evaluation times. The aim of this study is to improve the parallel performance using a new load balancing master-worker parallelization ...

    • A parallel three-dimensional radial basis function interpolation method for unstructured dynamic meshes 

      Estruch Pérez, Olga; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Pérez Segarra, Carlos David (2011)
      Conference lecture
      Open Access
      A radial basis function (RBF) interpolation method is implemented to be applied in computational fluid dynamics (CFD) problems with dynamic meshes. It is compared with the classic springs analogy smoothing, focusing on the ...

    • Algebraic linelet preconditioner for the solution of the Poisson equation on boundary layer flows 

      de Olazábal, Ramiro; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard (Barcelona Supercomputing Center, 2021-05)
      Conference report
      Open Access
      An algebraic linelet preconditioner is presented, which works in parallel regardless of the mesh’s geometry and without imposing constraints on the domain partition. It is designed to deal with highly anisotropic meshes. ...

    • Assessment of the symmetry-preserving regularization model on complex flows using unstructured grids 

      Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Rodríguez Pérez, Ivette María; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2012-05-15)
      Article
      Restricted access - publisher's policy
      The main objective of the present paper is the assessment of symmetry-preserving regularization models on unstructured meshes. Three different test cases have been studied: the impinging jet flow, the flow past a circular ...

    • Cache-aware sparse patterns for the factorized sparse approximate inverse preconditioner 

      Laut Turón, Sergi; Borrell Pol, Ricard; Casas Guix, Marc (Association for Computing Machinery (ACM), 2021)
      Conference report
      Open Access
      Conjugate Gradient is a widely used iterative method to solve linear systems Ax=b with matrix A being symmetric and positive definite. Part of its effectiveness relies on finding a suitable preconditioner that accelerates ...

    • CFD simulation of the thermal behavior of a wind mill power generator nacelle 

      Colomer Rey, Guillem; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio (2009)
      Conference lecture
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      In this work we use the Large Eddy Simulation model to predict the thermal behavior of the air inside of a wind generator nacelle, where several elements with di erent thermal characteristics are found. Outside air enters ...

    • Characteristics of the near wake region behind a cylinder at critical and super-critical Reynolds numbers 

      Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Chiva Segura, Jorge; Borrell Pol, Ricard; Oliva Llena, Asensio (Begell House, 2015)
      Conference report
      Restricted access - publisher's policy
      Large-eddy simulations (LES) of the flow past a circular cylinder are used to investigate the characteristics of the near wake region at Reynolds numbers Re = 2.5 × 105 - 8.5 × 105. This range encompasses both the critical ...

    • Coherent structures in a flow past a circular cylinder at critical and super-critical Reynolds numbers 

      Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Chiva Segura, Jorge; Borrell Pol, Ricard; Oliva Llena, Asensio (Springer, 2015)
      Conference report
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      It is well known that the wake topology in the flow past a circular cylinder remains almost unchanged up to Reynolds number ~105 Williamson (Annu Rev Fluid Mech 28(1), 477–539 (1996)) [1]. Then, at Re~2×105 major changes ...

    • Communication-aware sparse patterns for the factorized approximate inverse preconditioner 

      Laut Turón, Sergi; Casas Guix, Marc; Borrell Pol, Ricard (Association for Computing Machinery (ACM), 2022)
      Conference report
      Open Access
      The Conjugate Gradient (CG) method is an iterative solver targeting linear systems of equations Ax=b where A is a symmetric and positive definite matrix. CG convergence properties improve when preconditioning is applied ...

    • Direct numerical simulation of a NACA0012 in full stall 

      Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio (2013-10-15)
      Article
      Open Access
      This work aims at investigating the mechanisms of separation and the transition to turbulence in the separated shear-layer of aerodynamic profiles, while at the same time to gain insight into coherent structures formed ...

    • Direct Numerical Simulation of the flow over a sphere at Re = 3700 

      Rodríguez Pérez, Ivette María; Borrell Pol, Ricard; Lehmkuhl Barba, Oriol; Oliva Llena, Asensio; Pérez Segarra, Carlos David (2009)
      Conference lecture
      Restricted access - publisher's policy
      The direct numerical simulation of the flow past a sphere at Re=3700 is presented. The computations are carried out with a parallel unstructured symmetry preserving information for accurate solving complex geometries. As ...

    • Direct numerical simulation of the flow over a sphere at Re = 3700 

      Rodríguez Pérez, Ivette María; Borrell Pol, Ricard; Lehmkuhl Barba, Oriol; Pérez Segarra, Carlos David; Oliva Llena, Asensio (2011-05-19)
      Article
      Restricted access - publisher's policy
      The direct numerical simulation of the flow over a sphere is performed. The computations are carried out in the sub-critical regime at Re = 3700 (based on the free-stream velocity and the sphere diameter). A parallel ...

    • Direct numerical simulation of the flow over a spherical bubble in a turbulent pipe flow 

      Jofre Cruanyes, Lluís; Balcázar Arciniega, Néstor; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Castro González, Jesús (International Association for Computational Mechanics (IACM), 2014)
      Conference report
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      This work aims at investigating, by means of a direct numerical simulation, the flow over a clean spherical bubble fixed on the axis of a turbulent pipe flow. The simulation is performed by means of a parallel unstructured ...

    • Direct numerical simulation of the turbulent natural convection flow in an open cavity of aspect ratio 4 

      Chiva Segura, Jorge; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio (Begell House, 2012)
      Conference report
      Open Access
      In this paper, three-dimensional turbulent natural convection heat transfer in an open cavity with an isothermal wall facing the overture has been studied. The aspect ratio chosen for the cavity has been 4 to complement the ...

    • Direct numerical simulation of turbulent flows with parallel algorithms for various computing architectures 

      Gorobets, Andrei; Trias Miquel, Francesc Xavier; Borrell Pol, Ricard; Oyarzun Altamirano, Guillermo; Oliva Llena, Asensio (International Association for Computational Mechanics (IACM), 2014)
      Conference report
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      The purpose of the work is twofold. Firstly, it is devoted to the development of efficient parallel algorithms for large-scale simulations of turbulent flows on different supercomputer architectures. It reports experience ...

    • Direct numerical simulation of turbulent wakes: flow past a sphere at Re=5000 

      Rodríguez Pérez, Ivette María; Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Oliva Llena, Asensio; Pérez Segarra, Carlos David (2010)
      Conference report
      Open Access
      The flow around bluff bodies is of great interest for a large number of engineering applications such as vehicle aerodynamics, cooling devices using forced convection, heat transfer enhancement using droplets, among ...

    • Direct numerical simulations and symmetry preserving regularization simulations of the flow over a circular cylinder at Reynolds number 3900 

      Lehmkuhl Barba, Oriol; Borrell Pol, Ricard; Pérez Segarra, Carlos David; Chiva Segura, Jorge; Oliva Llena, Asensio (2009-09-14)
      Conference lecture
      Restricted access - publisher's policy
      Flow around cylindrical structures is of relevance for many practical applications. Knowledge of flow-related unsteady loading of such structures is crucial for hydro - and aerodynamic control and design. Recenty, the ...

    • Distributed tabulation of flamelet lookup tables 

      Abel, Nicholas; Borrell Pol, Ricard; Mira Martinez, Daniel (Barcelona Supercomputing Center, 2022-05)
      Conference report
      Open Access
      One of the fundamental questions in combustion simulation is how to account for detailed chemistry effects, while controlling both the error of the chemical scheme and the computational cost. Combustion chemistry is ...

    • Dynamic resource allocation for efficient parallel CFD simulations 

      Houzeaux, Guillaume; Badia Sala, Rosa Maria; Borrell Pol, Ricard; Dosimont, Damien; Ejarque Artigas, Jorge; García Gasulla, Dario; López Herrero, Víctor (Elsevier, 2022-09-15)
      Article
      Restricted access - publisher's policy
      CFD users of supercomputers usually resort to rule-of-thumb methods to select the number of subdomains (partitions) when relying on MPI-based parallelization. One common approach is to set a minimum number of elements or ...